Which capnograph

RE: Which capnograph

Rob Loxley — Sat, 05 Aug 2017 14:38:29 GMT

[quote user="Martin Atkinson"][quote user="robloxley"]we've had issues with the pulse ox clips breaking (which can't be bought separately to a new whole sensor, [/quote]Seems to be an issue with all pulse ox clips they are the bit most vulnerable to damage.[/quote]

We've had to replace the Surgivet (Smiths Medical made) clip once in 9 years, and it is a ~£20 part. We've replaced 3 Mindray clips in 9 months and once you've used the 2 it comes with, you have to buy a whole new probe set at >£150.

[quote user="Martin Atkinson"]It is also the one part of any monitoring that I find is the least reliable: often doesn't read when attached and still gives a reading when not! We use it as a guide to investigate further and don't rely on it.[/quote]

But if I've spent a few thousand on a machine I expect the build quality to be up to the task. We are careful with the items (see our other monitor) - the issue is stress fracturing of the plastic where the pivot hole goes through, though nobody will say whether it is just a batch issue.

RE: Which capnograph

Martin Atkinson — Sat, 05 Aug 2017 10:39:20 GMT

[quote user="robloxley"]we've had issues with the pulse ox clips breaking (which can't be bought separately to a new whole sensor, [/quote]Seems to be an issue with all pulse ox clips they are the bit most vulnerable to damage. It is also the one part of any monitoring that I find is the least reliable: often doesn't read when attached and still gives a reading when not! We use it as a guide to investigate further and don't rely on it.

RE: Which capnograph

Rob Davis — Sat, 05 Aug 2017 09:06:49 GMT

[quote user="robloxley"]as Mindray don't actually make such an accessory, the one that comes for the surgivet advisor (also a Burtons stocked item so they can get you that spare part) fits well[/quote]

As we have a Coltronics scavenging system, we were told we would need to contact them to get a suitable part. I've not worried about it so far, but will probably ask them when they next come to service the system.

We have only had the monitor for a couple of weeks, and are still getting used to it, but so far I and pleased, though I'm slightly concerned by your comment on the pulse oximeter clips.... time will tell.

RE: Which capnograph

Rob Loxley — Fri, 04 Aug 2017 21:23:12 GMT

[quote user="Rob Davis"]Do you use one robloxley?[/quote]

As the manual flagged it up (WARNING Anesthetics: When using the Sidestream or Microstream CO2 measurement on patients who are receiving or have recently received anesthetics, connect the outlet to a scavenging system, or to the anesthesia machine/ventilator, to avoid exposing medical staff to anesthetics); as Mindray don't actually make such an accessory, the one that comes for the surgivet advisor (also a Burtons stocked item so they can get you that spare part) fits well.
We have the monitor sat on a shelf on the anaesthetic trolley so there's not too much faff with the extra tube.

100ml/minute sampling is not a huge amount, probably similar to a leaky ET cuff, but worth fixing it entering the room?

I'm still in two minds about the machine - it not coming with a part for its safe functioning (according to the manual) niggles; also we've had issues with the pulse ox clips breaking (which can't be bought separately to a new whole sensor, and which while Burtons have acknowledged are an issue, neither them nor the manufacturer has provided replacements except just selling us a whole new sensor). The touch screen is however nice and the capnograph seems decent and it's a cute compact unit!

RE: Which capnograph

Rob Davis — Fri, 04 Aug 2017 19:27:00 GMT

We have recently bought the same machine and have had a conversation about the scavenging connector. It didn't come with one and we have been using it without so far, and I have yet to detect any isoflo. I suspect there is considerably more released into the room by animals recovering from GA, and having another bit of tubing to get in the way and get tangled up isn't appealing, so at the moment we are continuing without.

Do you use one Rob Loxley?

RE: Which capnograph

Martin Atkinson — Fri, 04 Aug 2017 14:41:34 GMT

[quote user="robloxley"]The capnograph is sidestream sampling and has a port on the side of the machine to connect to your scavenging system (else the iso/sevo in the capnograph sample is just released into the room), but no tubing or connectors are supplied to actually connect this up. Unless things have changed?[/quote]Hmmm.......you're correct. It seems this is at present just being vented into the room air. This was never mentioned when it was demoed and AFAIA no tube was provided or means of connecting into the scavenging system. Thanks for highlighting this issue I will have a word with Burtons. However the saving grace is that we have done a Coltronics gas monitoring since we started using it and exposure is still negligible.

RE: Which capnograph

Rob Loxley — Fri, 04 Aug 2017 13:52:11 GMT

[quote user="Martin Atkinson"][quote user="robloxley"]Did they include the capnograph exhaust pipe to connect into your scavenging system?[/quote] Otherwise I'm not sure quite how to answer your question other than...no.[/quote]

The capnograph is sidestream sampling and has a port on the side of the machine to connect to your scavenging system (else the iso/sevo in the capnograph sample is just released into the room), but no tubing or connectors are supplied to actually connect this up. Unless things have changed?

RE: Which capnograph

Martin Atkinson — Fri, 04 Aug 2017 10:17:08 GMT

[quote user="robloxley"]Did they include the capnograph exhaust pipe to connect into your scavenging system?[/quote] We use a closed circuit circle adsorber on a Steven's machine. The scavenging valve is positioned before the soda lime canisters and can be left open but this leads to an expensive waste of O2 and Iso. One of the advantages of the Stevens is the economics of being able to continually recycle these. Otherwise I'm not sure quite how to answer your question other than...no.

RE: Which capnograph

Rob Loxley — Thu, 03 Aug 2017 15:26:09 GMT

[quote user="Martin Atkinson"]we finally got a Mindray iMEC8Vet from Burtons[/quote]

Did they include the capnograph exhaust pipe to connect into your scavenging system?

RE: Which capnograph

Martin Atkinson — Thu, 03 Aug 2017 11:33:39 GMT

Bump.....The new thread on blood pressure monitors jogged me on this one so as an update we finally got a Mindray iMEC8Vet from Burtons. It dos all we want i.e. pCO2, pulse ox, BP, ECG, resp rate, temperature, seems reliable so far and the nurses love it. Only downside is battery life is not wonderful and it rarely lasts more than one operating session but its easy enough to plug into a floor socket while were working.

It has changed the way we use our anaesthetic machine as the inspiratory CO2 was consistently higher than recommended and we've drawn the conclusion that our O2 flow rate was too low on a circle circuit to produce enough back pressure to drive the expiratory pathway through the CO2 adsorber and use a smaller canister for cats and small animals.

RE: Which capnograph

Bob Russell — Sat, 20 May 2017 10:35:04 GMT

A capnograph helps tell me all is well! Nice regular patterns at a glance.

Anything changes at all - a signal to check and recheck everything!

I would absolutely hate to operate without one working in the background. It is just like any other monitor, a tool, just a really good one!

RE: Which capnograph

Anthony Todd — Sat, 20 May 2017 00:02:29 GMT

Thanks, yours and the reference explained most of it.

I was sort of thinking about Martin's case [and why] and how you could "breathe" ie, in effect hyperventilate the patient to lower pCO2 whilst maintaining anaesthetic depth so he could continue the op.

We had every, and all, of those "mechanical" or "plumbing" mishaps over the years but fortunately discovered them early enough or prior to GA, [usually!]

RE: Which capnograph

Beats — Fri, 19 May 2017 23:39:14 GMT

[quote user="Anthony Todd"]As I dinovet I'm more interested in how these instruments help during an anaesthetic ie what can, or do you, do if you see the CO2 rising etc., or is it just a case of lightening the anaesthetic ie reducing anaesthetic agent uptake, with any departure from any "normal" value?[/quote]

In basic terms, you have a respiratory monitor which detects CO2, and how much CO2.

To breathe out CO2 you need tissue metabolism, circulation to get CO2 to lungs, gas exchange and breathing. While mainly see elevated CO2 levels from hypoventilation (or no CO2 from not breathing), rapidly falling CO2 levels could tell you the patient is arresting (i.e. circulatory failure leading to lack of CO2 delivery to lungs).

The main purposes of this are simple safety-netting of human error:

tube in right place (must be otherwise won't get CO2)

endobronchial intubation

tube not blocked

tube connector not disconnected

respiratory arrest has occurred (spotted before cardiac arrest ensues allowing to breathe for patient)

the patient has become unnecessarily deep (breathing has slowed, is less deep and CO2 levels have risen as result)

the soda lime is exhausted (or indeed the soda lime cannister has been forgotten off the humphreys ade which is operating as a minilack on a labrador with flow rate of half a litre...): expired CO2 level rises and on inspiration does not reach baseline.

Patient is fat, hypothermic, has had a pile of opioids/alpha-2's etc and is hypoventilating: expired CO2 level rises.

patient has significant lung disease you weren't aware of affecting gas exchange (stop doing your elective procedure)

If the respiration is too slow or the CO2 is too high then:

a) check patient, connections and bag

b) check level of consciousness is appropriate (lighten if not)

c) breathe for the patient to provide adequate ventilation before tissue hypoxia of something important like the heart/brain/kidney occurs.

Like an ECG or doppler probe, a capnograph is also indispensible during CPR, if you already have it connected when your patient arrests then that's going to be pretty helpful during any resuscitation attempt.

see

http://capnography.com/

or the excellent 3 part series in Veterinary Nursing Journal from 1-2 years ago

for more technical details.

ultimately easier to learn about if already familiar with using day to day however rather than reading dry from a book.

RE: Which capnograph

Anthony Todd — Fri, 19 May 2017 23:09:18 GMT

As I dinovet I'm more interested in how these instruments help during an anaesthetic ie what can, or do you, do if you see the CO2 rising etc., or is it just a case of lightening the anaesthetic ie reducing anaesthetic agent uptake, with any departure from any "normal" value?

Would any of these instruments have helped in Martin's case??

My experience was that almost all anaesthetic disasters happened on induction rather than after long procedures??

RE: Which capnograph

Robert Lowe — Fri, 19 May 2017 19:38:12 GMT

Hi Martin

We have the EDAN units and some Vetronic ones. Eickemeyer do a unit that is remarkably similar to the EDAN and we have some of those as well. I would suggest not going with the basic EDAN capnography module but for the respironics capnography module as more reliable.

Vetronic have been great in the past and are neat little units but having some issues with post sales service at present.

Hope this helps

Rob

RE: Which capnograph

Bob Russell — Fri, 19 May 2017 11:08:54 GMT

We still live with our Datex Ohmeda Capnomac machine. 100's of years old but works wonderfully and I don't have the heart to replace it whatever the price!

It does not have a pulse ox but I find that pretty useless during surgery and a bit of a pain when moving a patient during recovery.

It does give iso levels as well.

Great big screen you can see from the other side of the room (I agree the pattern is probably of more value than the numbers) so I see it out of the corner of my eye however good the person is doing the monitoring!

Bad side? It has a memory failure problem so you can not longer use it to record things. Possibly requires a new internal battery to retain stuff!

Was £90 plus duty and the cost of a 110V step up converter (£30) from a supplier on ebay. Was sold with a dead on arrival guarantee five or more years ago!!

Portable units have stupid little screens and some of the bigger ones are so fussy that they appear more complicated than is needed!

RE: Which capnograph

Iain Richards — Fri, 19 May 2017 10:50:15 GMT

An absolute must is a good display for the capnograph, not just raw data. The shape is often more helpful as an early warning.

RE: Which capnograph

Martin Atkinson — Fri, 19 May 2017 10:28:39 GMT

Thanks Beats, but as suggested that is bit out of my league for a sole charge vet who is likley to be retiring in the next 2-3 years! I am looking at the Imec 8 which was mentioned earlier or something from Edan.

[quote user="Beats"]

In order of importance (i.e. which bits do you not mind if they're absent or a bit dud), rank the following for your preferred unit:

a) Capnography

b) Pulse oximetry

c) Blood pressure (oscillometric)

d) Temperature probe

e) ECG

f) Arterial blood pressure

[/quote]I would re-order your list and put BP at b) and ECG at c) - I can't help but feel that if we'd have seen an arrhythmia before cardiac arrest which would have helped, then the rest not in any particular order albeit arterial BP still last as it is in the real routinize surgery world unachievable. I would like to think pulse oximetry would rank higher but IME it is unreliable.

RE: Which capnograph

Beats — Fri, 19 May 2017 09:57:09 GMT

[quote user="Martin Atkinson"]The other equipment is not that reliable and it could be used in other rooms so a multiparameter unit with everything in one place is the favoured way to go for now.[/quote]

If it's a multiparameter unit you're looking for, then I think this is about as deluxe as you can get:

http://www.systemvet.com/products/vettrendsvetmonitor.html (I'm drooling)

but likely 2-4 times your budget I'm guessing...

Biggest issue with multiparameter units is oscillometric blood pressure that doesn't work, but if you've still got your doppler (which I personally prefer anyway as I like listening to heart rate while I'm operating) then you can always use that instead.

In order of importance (i.e. which bits do you not mind if they're absent or a bit dud), rank the following for your preferred unit:

a) Capnography

b) Pulse oximetry

c) Blood pressure (oscillometric)

d) Temperature probe

e) ECG

f) Arterial blood pressure

Ex-hospital units can be bulky but otherwise excellent - just check the sampling volume and rate for the capnography, whether the pulse ox probe is reliable in cats/dogs and whether you can still get filters for the capnograph at affordable prices etc etc...

RE: Which capnograph

Martin Atkinson — Fri, 19 May 2017 09:18:13 GMT

Thanks everyone for your replies, some very useful information/advice from everyone but I've picked a few for replies:

[quote user="Gillian Mostyn"]Sorry to hear that Martin. Must have been a tough day for you. No matter how long you do this job, stuff like that gets to you. Hope you're ok.[/quote]Thanks but I'm fine, I've seen enough shit in 42 years not to be anything other than frustrated and sorry for the owners. I can just put it in the hurt locker and move on but I feel for my nurse who was monitoring, was inconsolable and will of course blame herself even though she did nothing wrong and this is her first disaster.

[quote user="robloxley"]Genuine tangent to you tangent, how would the capnograph have helped this case, do you think?[/quote] With the brief demonstrations/reviews of capnographs I've seen, the PCO2 is a lot more sensitive and gives better advance warning than other parameters. We'd already got a reduced BP and falling O2 sats which alerted us to start changing the drip rate and Iso level but it may have alerted us sooner.

[quote user="Anthony Todd"]What happened and why? Will almost certainly help others.[/quote]I've given a brief description of the preceding events and it was responding with a increased BP and pulse ox when we quickly realised it had stopped breathing and there was no heart beat, all within a minute or so. Without a PM exam one has to assume that a young apparently healthy dog which was being maintained and monitored like thousands before with no mishap had an underlying heart condition and just had a cardiac arrest.

[quote user="robloxley"] I have however had issues with the pulse-ox clips, [/quote]I don't trust pulse ox clips so that would probably not be on big loss.

[quote user="Beats"]If you already have all your other monitoring equpiment available, then I'd get a standalone unit rather than multiparameter most likely.[/quote]The other equipment is not that reliable and it could be used in other rooms so a multiparameter unit with everything in one place is the favoured way to go for now.

RE: Which capnograph

Anthony Todd — Thu, 18 May 2017 23:54:45 GMT

[quote user="Beats"]You can certainly do that with the relatively inexpensive model I use,[/quote]

Be handy to see the trace before a catastrophe, particularly if the values were all fine 'til the end which can happen in humans I think.

[I always thought listening to the heart was distracting and a waste of resources as when the heart stops it's usually far too late.]

RE: Which capnograph

Beats — Thu, 18 May 2017 23:41:53 GMT

[quote user="Anthony Todd"]Is there one made that you can recover the data from, or you can attach a memory stick so you can record then playback??[/quote]

You can certainly do that with the relatively inexpensive model I use, but requires a purchase of a specific memory stick.

I don't know how universal that feature is.

RE: Which capnograph

Anthony Todd — Thu, 18 May 2017 23:16:54 GMT

Sorry dupl again!

RE: Which capnograph

Anthony Todd — Thu, 18 May 2017 23:15:51 GMT

[quote user="Beats"]Like buying a house, you need to decide on your compromises.[/quote]

Is there one made that you can recover the data from, or you can attach a memory stick so you can record then playback??

RE: Which capnograph

Beats — Thu, 18 May 2017 23:00:47 GMT

Martin,

re capnograph:

do you want a portable unit that you can use during induction, dental area, theatre, recovery in kennel or a fixed unit in one of those locations (or a semi-fixed unit in a location but it can be moved with little hassle if needed but more effort than you're likely to go to on a day-to-day procedure)?

Like buying a house, you need to decide on your compromises.

The ideal unit is set up and ready to go all the time, has a big screen so you can see it while scrubbing up etc, can be used in any of those locations (so either lots of machines or at least one portable one), has minimal running costs, works well, doesn't take up too much space, works with cats, doesn't take up too much dead space, is easily scavenged (if side-stream).

You need to decide side-stream or mainstream capnography.

If you already have all your other monitoring equpiment available, then I'd get a standalone unit rathre than multiparameter most likely.

I'd suggest buying 2 units may be worth considering: a £800 Nonin sidestream with DIY scavenge (new standalone units never seem to have scavenge as designed for use in ambulances etc not an operating theatre where multiparamenter models will be used in hospitals) that is velcro-d to theatre GA workstation is all I have - big screen, reasonable runnign costs and ease of buying filters, works well generally but can be bit unreliable on cats breathing spontaneously. I'd buy an EMMA (Masimo) or capnovet-10 (Vetsonic) to supplement this if I was allowed as in real terms I rarely detach it to take to other parts of clinic and mainstream is possibly more practical for mobile unit available for dentals, induction, post-op recovery, CPR, xray etc. i dislike running backwards and forwards to theatre with monitoring equipment used during indcution, so my preference by far would be multiparameter fixed unit in theatre, but spending all cash on that and then having less monitoring for (eg dentals) doesn't really make sense.

I looked into this a few years ago so happy to look at specs of anything you spy re sampling rate and volume of sampling etc if sidestream to see if suitable for cats etc.